This is a competitive renewal of a training program in Genetics and Developmental Biology at Stanford University. The grant currently supports 10 students who train among 57 distinguished faculty from two highly interactive departments. The faculty and trainees have a remarkable record of landmark contributions to the fields of genetics, genomics, and developmental biology. These include: the invention of recombinant DNA methods; the first molecular studies of developmental mutations in flies; the discovery and elucidation of the homeobox, Wnt, BMP, and hedgehog signaling pathways; the mechanistic study of RNAi pathways; the large- scale mapping and sequencing of microbial, fish, and mammalian genomes; the application of genome-wide expression analysis in bacteria, yeast, worms, flies, and humans, and the purification of many kinds of stem cells. We have also pioneered the development of several new model organisms for studying key problems in biology, including mechanisms of cellular asymmetry, vertebrate evolution, plant and animal domestication, and the control of lifespan in natural species. In each case, major progress has depended on combining genetic, genomic, and developmental approaches. In the current era, we believe that similar interdisciplinary training is more important than ever. High-throughput sequencing and massive studies of genetic variation are currently transforming much of biomedical research. However, connecting DNA sequence to traits remains a key challenge for researchers in all fields. Our training program directly addresses the problem of mapping genotypes to phenotypes by offering combined training in genetics and genomics, as well as experimental methods for examining gene function in a wide range of both model and non-model organisms. This grant has led to the development of many special features that are now hallmarks of graduate student training in our program, including: coordinated admissions, a joint training camp combining computational and experimental methods, core courses, joint teaching, flexible research rotations during the first year, joint advising, joint journal clubs and research seminars, and major curricular innovations now underway to encourage interdisciplinary training. By all measures, the program has been highly successful. We receive an exceptional number of applicants for the limited number of positions available, can accept only 4% of applicants, and have successfully enrolled over 70% of accepted students in the last two years. Over 90% of admitted students successfully progress to the Ph.D., and our average time to graduation has been falling in response to a renewed focus on career preparation and timely completion of thesis research. Impressively, the 215 Ph.D. students who have completed their training in the last 10 years have produced nearly 800 publications in leading journals. Most importantly, our trainees are embracing a full range of genetic, genomic, computational, and experimental approaches, often combining techniques from different disciplines to make major research advances, while at the same time bringing the benefits of these advances to applications in the clinical realm.